So the Raine family were devastated when one of their passports disappeared at check-in just minutes after they had handed it over – forcing them to abandon their £5,500 trip to Florida.

Alan Raine, 54, believes the check-in worker at Manchester airport knocked the passport on to the baggage conveyor and that it disappeared into the maze of the airport’s luggage system.

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Grounded: Alan Raine (second from right) and his family missed out on their dream holiday to Florida

When he suggested this, he was told it was ‘impossible’ – but his theory gained some weight when the passport turned up the next day on a baggage carousel at arrivals.

Mr Raine had spent 13 months planning the two-week trip and had booked tickets to theme parks including Universal Studios for himself and his wife Yvette, 49, their 28-year-old son Ashley, grandson Ryan, eight, and Mrs Raine’s retired parents Malcolm and Yvonne Bowes, who are 74 and 73.

'Sorry': United Airlines says it will contact the family and offer a gesture of goodwill

He added that he was furious about the reaction of United Airlines, which was operating the flight, claiming the family is yet to receive an apology. ‘We are annoyed at the way they have gone about it,’ he said.

‘They have told us they are investigating but we haven’t heard anything. They don’t seem interested.

‘I was just flabbergasted at the attitude of the staff. I actually said to them: “Do you realise what we are losing here?”’

The family, from Bishop Auckland, County Durham, had already shown all six of their passports at a minor security check when they arrived at the airport last Monday. But when they handed over the documents at check-in, they were stunned when the worker said Ashley’s was missing.

After they complained, the family were told that an employee of Swissport, which runs the airport’s baggage system, would carry out a ‘thorough search’.

But Mr Raine said this lasted for only two minutes.

Ashley Raine's missing passport turned up on the baggage carousel in arrivals the next day

When the passport could not be found, they were offered later flights if they could get an emergency passport, but Mr Raine said it was impossible to get a new one in time.

The Raines had to abandon the trip because they did not want to leave Ashley, a civil engineer, behind, especially as it would leave Ryan without his father.

A spokesman for United Airlines said: ‘We are sorry to hear about the disruption to the Raines’ family travel plans following the loss of a passport at Manchester airport.

‘United will contact the customer to offer a gesture of goodwill.’

The Raines said they have yet to be contacted by the airline.

Swissport said: ‘United Airlines is investigating what has happened in association with Swissport, and when this is completed they will be in touch with the family.’